Molecular hydrogen is a very attractive environmentally friendly fuel. It reacts with oxygen in a highly exothermic reaction having a relatively low activation barrier. The by-product of this oxidation reaction is water. The use of hydrogen does not produce so-called green house gas by-products. Hydrogen currently is being used as fuel for propelling the space shuttle into orbit.
Despite the many advantages of the use of hydrogen as a fuel source, hydrogen has not found its place as a mainstream transportation fuel. The major setback for the use of hydrogen appears to be the same properties that make it attractive as a fuel source. Hydrogen is a highly flammable gas whose reaction with oxygen releases a great deal of energy. Any uncontrolled reaction of hydrogen with oxygen is, therefore, invariably explosive. Storage of sufficient amounts of hydrogen in a vehicle to power it for a standard trip on a tank-full of fuel, approximately 300 miles, puts the occupants of the vehicle in a precariously dangerous position if the vehicle encountered an accident that would cause the hydrogen tank to rupture. This tragedy was witnessed when the space shuttle Challenger exploded over the Atlantic Ocean in 1986.
The solution to the above problem appears to be the in situ generation of hydrogen from sources that can provide large quantities of hydrogen on demand, while in themselves do not react uncontrollably with oxygen. The hydrogen source, and the by-products of hydrogen generation, should both be easily disposable and environmentally friendly.